Various systems are known for supporting loads on roofs, and for installing skylights and/or smoke vents onto, into roofs.
Commonly used skylighting systems have translucent or transparent closure members, also known as lenses, mounted on a support structure which extends through an opening in the roof and is mounted to building support members inside the building. Ambient daylight passes through the lens and thence through the roof opening and into the building.
Thus, conventional skylight and smoke vent installations use a complex structure beneath the exterior roofing panels and inside the building enclosure, in order to support a curb which extends through the roof and supports the skylight lens. Conventional skylight curbs, thus, are generally in the form of a preassembled box structure surrounding an opening which extends from the top of the box structure to the bottom of the box structure. Such box structure is mounted to building framing members inside the building enclosure, and extends through a respective opening in the roof, similar in size to the opening which extends through the box structure. The skylight assembly thus mounts inside the building enclosure, and extends through an opening in a separately mounted roof structure. Fitting skylight assemblies into such roof opening, in a separately-mounted roof structure, presents problems. All known conventional structures have a tendency to leak water when subjected to rain.
In light of the leakage issues, there is a need for a more effective way to support skylights and smoke vents, thus to bring daylight into buildings, as well as a more effective way to support a variety of other loads, on roofs.
To achieve desired levels of daylighting, conventional skylight installations use multiple roof openings spaced regularly about the length and width of a given roof surface through which daylight is to be received. Each skylight lens is installed over a separate such opening; and the opening for each such skylight assembly, each representing a single lens, extends across multiple elongate metal roof panels.
The opposing sides of conventional metal roof panels, to which skylight assemblies of the invention are mounted, are raised above elongate centralized panel flats which extend the lengths of the panels, whereby the sides of adjacent such roof structures are joined to each other in elongate joints, referred to herein as ribs. The opening for a conventional skylight cuts across multiple such ribs in order to provide a large enough opening to receive conventionally-available commercial-grade skylight assemblies. The skylight assembly, itself, includes a curb which is mounted inside the building and extends, from inside the building, through the roof opening and about the perimeter of the opening, thus to support the skylight lens above the flats of the roof panels, as well as above the ribs. Conventional pliable tube construction sealants are applied about the perimeter of the roof opening, between the edges of the roof panels and the sides of the skylight assembly curb, including at the cut ribs. Typically, substantially all of such sealant is applied in the panel flats, which means that such sealant is the primary barrier to water leakage about substantially the entire perimeter of the skylight curb. One of the causes of roof leaks around the perimeter of conventional roof curbs which attach primarily through the panel flat at the water line is due to foot traffic, such as heel loads or other dynamic loads imposed by workers wheeling gas cylinders or other heavy equipment on the roof panel e.g. with dollies. This type of dynamic loading can cause high levels of stress on the joints that rely solely on tube sealant to provide seals in the wet areas, namely in the panel flats. Such leaks are common around fastener locations as the panels flex under load and cause the sealant to deform such that, in time, passages develop through the sealant, which allows for the flow of water through such passages.
Such multiple curbs, each extending through a separate roof opening, each sealed largely in the panel flats, create multiple opportunities for water to enter the interior of the building. Applicants have discovered that such opportunities include, without limitation,                (i) the number of individual openings in the roof,        (ii) the widths of the openings which require cuts through the multiple ribs,        (iii) the tendency of water to collect and stay at the upper end of the curb,        (iv) the disparate expansion and contraction of the roof panels relative to the skylight curb; and        (v) the lengths of sealed seams in the panel flats.        
The traditional curb constructions and methods of attachment in most cases thus require that a complicated support structure be installed below the metal roofing and inside the building enclosure, which allows disparate/discordant movement of the metal roof panels and the skylight assembly relative to each other, as associated with thermal expansion and contraction of the metal roof e.g. in response to differences in temperature changes inside and outside the building.
In addition, conventional curb-mounted skylights tend to accumulate condensation, especially about fasteners which extend from the outside of the building to the inside of the climate-controlled building envelope.
Thus, it would be desirable to provide a skylight system which provides a desired level of daylight in a commercial and/or industrial building while substantially reducing the incidence/frequency of leaks occurring about such skylights, as well as reducing the incidence/frequency of condensate accumulation in the areas of such skylights.
It would also be desirable to provide a smoke vent system while substantially reducing the incidence/frequency of leaks occurring about such smoke vents, as well as reducing the incidence/frequency of condensate accumulation in the areas of such smoke vents.
It would further be desirable to provide a support system, suitable for supporting roof loads, up to the load-bearing capacity of the metal roof while substantially controlling the tendency of the roof to leak about such support systems, as well as reducing the incidence/frequency of condensate accumulation in the areas of such closure support systems.